Compound plug



Nov. 18, 1924- 1,515,661 W. M. CROSS y coMPoUND PLUG l Filed Feb. 18, 1920 'I P'aieiaed Nov. is, 1924.

PATENT OFFICE.

WALTER M. CROSS, 0F KANSAS CITY, MISSOURI.

comrounn nos.

Application mea February 1s, mab. seria-fno.l 359,642.

To all whom it may'cohcem:

Be it known that I, WAUrna vM. Cnoss,

a citizen of the United States, residing in Kansas City, county of Jackson, and State of Missouri, :have invented certain new and useful Improvements in CompoundA Plugs, of which the following is a specification..

My invention relates to improvements. in compound plugs and refers more particularlyA to a typeof plug adaptable to. boilers, pipe coils -or the like where pipes or. ilues must be opened to be cleaned. Among its salient objects are to `provide a plug constructed in sections or parts, it being necessary to, remove the entire plug only when a tube or pipe is to be replaced, the removal of the inner members of the plug permitting easy access tothe tubes or pipes to be cleaned; to provide aplug which maybe easily removed irrespective of the heat to which the system (of which it is a part) has been subjected or the character of the material or substance treated therein;

to provide a plu that eliminates the inconvenience and difficulties attending the remova'l of the common type of plug and one that obviates the dangers accompanying stripped or disintegrated threads usual in plugs commonly used where heat and pressure are concerned to provide a plug that is comparatively cheap in construction and Ainvaluable as regards safety and ease of insertion and removal and in general to provide a plug ofthe character referref to. In the drawings v In Fig. 1 at A is shown the plug in side elevation screwed into a pipe coilheader. At B is shown a like plug in cross section. At C is shown-the plug in cross section with the head screw and plug nut omitted and' a handfbolt vinserted for removing the obturator. y Fig. 2 is a face view of the obturator. In all types of boilers, pipe coils or heating means where tubes are used for the pur-t pose of heating liquids or vapors, it is' common to have some provision for the cleaning ofthe tubes or pi es. The most usual means in this type o equipment are p1pe plugs which are threaded and inserted 1n the ends of the respective tubes-or in the headers which cpnnect the tubes. Where a high degree of heat is used in any particular process and where pressure is concerned, diiculties are encountered with these plugs, both with their removal andthe danger accompanying the disintegration and strip-v ping of the threads, duefto-the action o the liquids or vapors upon the threaded portion and the force required in inserting the plugs to make them gas or liquid-tight.

Referring in detail tothe drawings, the

pipes 1 are connected to a header 2 in which are shown three plugs considered as a Whole at 3 and placed in a position so that when they are removed the pipesdirectly opposite them ma `be cleaned.

The p ug 3 comprises a bushing 4, obturator 5, plug nut 6 and ahead screw 7. The bushing 4 is threaded externally at 8 and Ais adapted to be screwed into the header y 2. It is unnecessary'to remove this bushing from the header except when one of the tubes is to be removedtherefrom. A gasket 9 is placed between the header and the bushing to ass-urel a gas-tight. joint. At 10, the bushing is internally `threaded to receive the nut 6. A bevel seat 11 is ground into the-interior of the bushi turator member 5, which is similarly ground at 1.2 to fit the seat within the bushing. This obturator is bored and threaded to reat any suitable angle and is adapted to receive the obceive the removingbolt 13, which is usedA to remove the obturator after the lug nut and head screw have been taken rom the bushing.

At this time, it is-only necessary to tap the removing bolt so that the oby turator will be broken from its seat.

The plug nut isl externally threaded to be screwed into the bushing and bevelled at 6 to force the obturator firmly upon its ground seat. It is internally threaded to receive the head screw 7, which extends through the plug nut and sets against the grooved portion 12 on the surface of the obturator, thereby assisting the plug n'ut in seating the obturator and preventing the backing oil of the plug nut from the outerbushing. When it 1s necessary to clean the tubes, the head screw and plug nut may be easily removed as they are not subjected to the heat and ressure of the systemand consequently their threads are not aected by the same amount of contraction and eX- pansion and other disintegrating factors as the threads of the outer bushing. Aftery the removal of these holding members the removing screw 13 is screwed into the obturator and the latter easily broken from its ground seat within the bushing. These members may be removed by hand, no

matter what conditions of heat and pressure the system has been subjected to and obviate the necessity of powerful machines v 1. A removable closure for tube headers comprising a closure member adapted to be seated in a cleaning aperture, a holding member positioned behind the closure member for holding the same' in place, means on the interior of the' cleaning aperture by which the holding member isheld,I and a second holding member screw-threaded into the first holding member.

2. A removable closure for pipe ortube headers comprising a removable closure member adapted to be seated in a cleaning aperture, double holding members positioned behind the closure member for holding it rigidly in position, and means'on the interior of the c eaning aperture by' which one of the holding members is held in position.

3. A. removable closure for pipe and tube headers comprising a removable closure member adapted to be seated in a cleaning aperture, holding members ositioned behind said closure member, an means on the interior of the cleaning aperture to which one of the holding members is attached, one of said holding members contacting said closure member to hold it in position, the` other of said holding members eing adapted to impose additional (pressure upon the closure member and hol it rigidly on its seat. v

4. A compound plug of the character described, comprising a bushing externallyl e misent the obturator irml upon its seat, a head screw adapted to ho d the obturator in place and prevent the loosening of the plug nut.

5. A compound plug of the character described, comprising a threaded bushing adapted to be screwed in a pipe or header, an obturator seated therein, a lug nut screwed into the bushing and a apted to hold the obturator in osition, a head screw passing through the p ug nut setting against the obturator and preventing the plug nut from backing 0E.

6. A. compound plug of the character described, comprising an outer bushing threaded externally at one end and internally on the opposite end and having a seat intermediate of its ends, an obturator adapted to be seated thereon, a plug nut, in-

ternally and externally threaded, screwedv surface and adapted to be set in the cleaning holes of a pipe coil, a plug nut adapted to hold the obturator in position, a head screw passing through the plug nut setting against the obturator and preventing the pl ug nut from backing olii,

WALTER M. CROSS. 

